IBM Personal System/2 60 User Manual

Bito When set to 1, this bit enables the daylight savings time
mode. When set to 0, it disables the mode, and the clock
reverts to standard time. The system initializes this bit to
0.
Status Register C (Hex 00C)
Bit Function
7 Interrupt Request Flag
6 Periodic Interrupt Flag
§ Alarm Interrupt Flag
4 Update-Ended Interrupt Flag
3-0 Reserved
Figure 3-12. Status Register C
Note: Interrupts are enabled by bits 6, 5, and 4 in Status Register B.
Bit7 This bit is used in conjunction with bits 6, 5, and 4. When
set to 1, this bit indicates that an interrupt has occurred;
bits 6, 5, and 4 indicate the type of interrupt.
Bit6 When set to 1, this bit indicates that a periodic interrupt
occurred.
Bit 5 When set to 1, this bit indicates that an alarm interrupt
occurred.
Bit 4 When set to 1, this bit indicates that an update-ended
interrupt occurred.
Blts3-0 Reserved.
Status Register D (Hex 00D)
Bit Function
7 Valid RAM
6-0 Reserved
Figure 3-13. Status Register D
Bit7 This read-only bit monitors the power-sense pin. A low
State of this pin indicates a loss of power to the real-time
clock (dead battery). When set to 1, this bit indicates that
the real-time clock has power. When set to 0, it indicates
that the real-time clock has lost power.
Bits6-0 Reserved.
Model 60 System Board — October 1990 3-15

IBM Personal System/2 60 Specifications

General

Brand	IBM
Model	Personal System/2 60
Category	Desktop
Language	English